This morning at 5-45 amthe first muezzin called me. I went to the computer instead.

I am happy to be woken by the braying loudspeakers. Turkey is enchanting, and I cannot wait to get going. Normal sleepers waste so much time. I love the joking courtesy of people in markets, shops and streets, to each other as well as to tourists. I love the food, the unexpected cleanliness and absence of litter.

And everywhere the architectural evidence of power, and the inevitability of succession. Shelley’s Ozymandias comes to most minds that have even partly stored it (‘look on my works ye mighty and despair….’).

How does H Clark visit this region for her ANZAC pieties without renouncing her 60’s and 70’s student union worldview, that everything would be ‘benign’ if only the perfidious Americans could suffer defeat?

The saddest days in this region were when power was uncertain, Perceived weakness drew in destruction and enslavement, in cycle after cycle. The golden periods (expanding populations, monument and utility building) were when rulers were confident.They could then exile war and strife to the outer boundaries of their empires, where their people were the inflictors, not the victims.

There is a more alarming message from this history. It is not new, but our effete classes have removed it from our safety-dominated syllabus. Rich, learned, sophisticated, security obsessed peoples are often subjugated by single-minded primitive inferiors. Empires fall to tougher, more resilient people who make war their preoccupation.

What is it about Central Asia? We were shown Viking graffiti in the Hagia Sofia, butthey were overnight visitors. The Turks came from Central Asia and stayed, ushering in dark ages for large swathes of this region. We’ve visited site after site along this Turkish coast where great cities housing up to 250,000 people became desolate quarries for local populations of a few thousand. The subsistence scratching survivors housed themselves in huts with stone walls incorporating marble lintels, and pediments and capitals from buildings they could scarcely imagine.

Warriors from Central Asia destroyed Rome. Mongols burned Baghdad. They drove successive Chinese empires into their bad centuries of ‘warlordism’. After the Turks over-ran this country the Ottoman capital became great, but it could not match glorious Byzantium. The Turks found reading and writing to be important only after they acquired an empire to rule, but too late for much of the knowledge.

The invaders destroyed the great library at Pergamon (which invented books with pages instead of scrolls, and competed with Alexandria) because they reaoned (in the words of our guide) “ if the books have the same knowledge as the Holy Koran they do not need it, and if it is different it is wrong”.

The Romans could make concrete, and build a dome not matched until St Paul’s in the 18th century, and effective sewage systems.So much knowledge went up in smoke. Not just of philosophy and medicine. Concrete making knowledge vanished. The slaughter was so great that until recently the dry and faded inhabitants of Istanbul did not even know about the enormous underground water storage cisterns built by Justinian 1500 years ago, though they were still there, and still held water.